IVY Classic's HingeLoc Fixed Utility Knife features a twist knob which opens knife while remaining hinged at the back for easy blade changes. The double interlocking knife design holds the blade securely and prevents slipping. The all metal aluminum die-cast construction includes a heavy-duty utility blade and an internal magnet that accurately positions the blade for effort-free blade changes. The knife cuts drywall, roofing materials, linoleum, carpet and vinyl. The knife fits . 025" thick IVY Classic blades 11172 and 11178, and other heavy-duty utility blades. Hinge-Loc is a Registered Trademark.